<template>
  <div>
    <!-- 评论列表 -->
    <div class="cmt-list">
      <van-list
        v-model="loading"
        :finished="finished"
        finished-text="没有更多了"
        :immediate-check="false"
        @load="onLoad"
      >
        <!-- 评论的 Item 项 -->
        <div class="cmt-item like-box" v-for="(item, index) in commentList" :key="index">
          <!-- 头部区域 -->
          <div class="cmt-header">
            <!-- 头部左侧 -->
            <div class="cmt-header-left">
              <img :src="item?.aut_photo" alt="" class="avatar" />
              <span class="uname">{{ item?.aut_name }}</span>
            </div>
            <!-- 头部右侧 -->
            <div class="cmt-header-right">
              <van-icon
                name="like"
                size="16"
                color="red"
                v-if="item?.is_liking"
                @click="likeFn(item.is_liking, item)"
              />
              <van-icon
                name="like-o"
                size="16"
                color="gray"
                v-else
                @click="likeFn(item.is_liking, item)"
              />
            </div>
          </div>

          <!-- 主体区域 -->
          <div class="cmt-body">
            {{ item?.content }}
          </div>
          <!-- 尾部区域 -->
          <div class="cmt-footer">{{ timeAgo(item?.pubdate) }}</div>
        </div>
      </van-list>
    </div>
    <div>
      <!-- 底部添加评论区域 - 1 -->
      <div class="add-cmt-box van-hairline--top" v-if="hairline">
        <van-icon
          name="arrow-left"
          size="0.48rem"
          @click="$router.back()"
          color="#000"
        />
        <div class="ipt-cmt-div" @click="toggleshow">发表评论</div>
        <div class="icon-box">
          <van-badge :content="contentLength===0?'':contentLength" max="99">
            <van-icon name="comment-o" size="0.53333334rem" color="#000"  @click="getlikeFn"/>
          </van-badge>
          <van-icon name="star-o" size="0.53333334rem" color="#000" @click="isShowicon=!isShowicon" v-if="isShowicon"/>
          <van-icon name="star" size="0.53333334rem" color="wheat" @click="isShowicon=!isShowicon" v-else/>
          <van-icon name="share-o" size="0.53333334rem" color="#000" @click="$router.go(-1)"/>
        </div>
      </div>
      <!-- 底部添加评论区域 - 2 -->
      <div class="cmt-box van-hairline--top" v-else>
        <textarea placeholder="友善评论、理性发言、阳光心灵" v-focus @blur="blueFn" v-model="comtxt"></textarea>
        <van-button type="default" :disabled="comtxt.length===0" @click="sendFn">发布</van-button>
      </div>
    </div>
  </div>
</template>
<script>
import {
  commentListAPI,
  commentLikingAPI,
  commentDisLikingAPI,
  sendCommentAPI
} from '@/api/index'
import { timeAgo } from '@/utils/day.js'
import { Toast } from 'vant'
let timer = null
export default {
  name: 'commrntList',
  props: {
    artId: {
      type: String
    }
  },
  data () {
    return {
      art_Id: '',
      offset: null, // 评论的偏移量
      commentList: [], // 评论列表
      contentLength: null,
      hairline: true,
      loading: false,
      finished: false,
      comtxt: '', // 发布
      isShowicon: true
    }
  },
  /**
  通过props接受的==>this.artId  有一个坑！！！！！
  artId是通过父组件的axios请求回来的数据，在子组件自己的props里面接受的，但是axios是异步任务，子组件的beforcreated,created,beformounted,mounted优先于父组件的异步任务，so 在子组件的created通过this.artId拿到的数据是underfind，只有通过监听，判断父组件数据请求回来后，给自己赋值了，再拿这个值做相对的逻辑处理
*/
  watch: {
    artId: {
      handler (newval) {
        if (newval) {
          this.art_Id = newval
        }
      }
    },
    immediate: true,
    deep: true
  },
  created () {
    this.art_Id = this.$route.query.art_id
    this.gtecommentList()
  },
  methods: {
    // 自己再练习一遍防抖
    fangdou (callback) {
      clearTimeout(timer)
      timer = setTimeout(() => {
        if (callback) {
          callback()
        }
      }, 500)
    },
    timeAgo,
    // 1.0 获取评论数据
    async gtecommentList () {
      await commentListAPI({ artId: this.art_Id, offset: this.offset }).then((res) => {
        const {
          data: {
            data: { results }
          }
        } = res || []
        if (results.length === 0) {
          // 没有评论
          this.finished = true
        }
        this.commentList = [...this.commentList, ...results]
        this.contentLength = res.data.data.total_count
        this.offset = res.data.data.last_id
        this.loading = false // 加载结束
        const count = this.commentList.length
        if (count >= this.contentLength) {
          this.finished = true
        }
      })
    },
    // 2.0 点击心心产生的操作
    async likeFn (boon, obj) {
      if (boon === false) {
        // 喜欢
        // 2.2 心心---不稀罕==>喜欢
        await commentLikingAPI({ comId: obj.com_id }).then((res) => {
          if (res.status !== 201) Toast.fail('点赞失败')
          obj.is_liking = true
          Toast.success('点赞成功')
        })
      } else {
        // 取消喜欢
        // 2.1 心心---喜欢==>不稀罕
        await commentDisLikingAPI({ comId: obj.com_id }).then((res) => {
          if (res.status !== 204) Toast.fail('取消失败')
          obj.is_liking = false
          Toast.success('取消成功')
        })
      }
    },
    // 3.0 点击发表评论
    toggleshow () {
      this.hairline = false
    },
    // 触底加载
    onLoad () {
      this.gtecommentList()
    },
    // 4.0 likeFn点击滑动到评论区
    getlikeFn () {
      // 真实DOM都在document(所以不再一个vue文件内), 也是可以获取的
      document.querySelector('.like-box').scrollIntoView({
        behavior: 'smooth'
      })
    },
    // 失去焦点
    blueFn () {
      setTimeout(() => {
        this.hairline = true
      }, 300)
    },
    // 点击发布按钮
    async sendFn () {
      await sendCommentAPI({ Id: this.art_Id, content: this.comtxt }).then(res => {
        if (res.status !== 201) return Toast.fail('评论失败')
        this.comtxt = ''
        // 在开头新增评论
        this.commentList.unshift(res.data.data.new_obj)
        this.contentLength++
        Toast.success('评论成功')
        this.getlikeFn()
      })
    }
  }
}
</script>

<style scoped lang="less">
.cmt-list {
  padding: 10px;
  margin-bottom: 40px;
  .cmt-item {
    padding: 15px 0;
    + .cmt-item {
      border-top: 1px solid #f8f8f8;
    }
    .cmt-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      .cmt-header-left {
        display: flex;
        align-items: center;
        .avatar {
          width: 40px;
          height: 40px;
          background-color: #f8f8f8;
          border-radius: 50%;
          margin-right: 15px;
        }
        .uname {
          font-size: 12px;
        }
      }
    }
    .cmt-body {
      font-size: 14px;
      line-height: 28px;
      text-indent: 2em;
      margin-top: 6px;
      word-break: break-all;
    }
    .cmt-footer {
      font-size: 12px;
      color: gray;
      margin-top: 10px;
    }
  }
}
/*美化 - 文章详情 - 底部的评论页面 */
// 外层容器
.art-cmt-container-1 {
  padding-bottom: 46px;
}
.art-cmt-container-2 {
  padding-bottom: 80px;
}

// 发布评论的盒子 - 1
.add-cmt-box {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  box-sizing: border-box;
  background-color: white;
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 46px;
  line-height: 46px;
  padding-left: 10px;
  .ipt-cmt-div {
    flex: 1;
    border: 1px solid #efefef;
    border-radius: 15px;
    height: 30px;
    font-size: 12px;
    line-height: 30px;
    padding-left: 15px;
    margin-left: 10px;
    background-color: #f8f8f8;
  }
  .icon-box {
    width: 40%;
    display: flex;
    justify-content: space-evenly;
    line-height: 0;
  }
}

.child {
  width: 20px;
  height: 20px;
  background: #f2f3f5;
}

// 发布评论的盒子 - 2
.cmt-box {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 80px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  padding-left: 10px;
  box-sizing: border-box;
  background-color: white;
  textarea {
    flex: 1;
    height: 66%;
    border: 1px solid #efefef;
    background-color: #f8f8f8;
    resize: none;
    border-radius: 6px;
    padding: 5px;
  }
  .van-button {
    height: 100%;
    border: none;
  }
}
</style>
